| 1. |
- Arvidsson Rådestig, Maya, et al.
(författare)
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Cerebrospinal fluid biomarkers of axonal and synaptic degeneration in a population-based sample
- 2023
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Ingår i: Alzheimers Research & Therapy. - : Springer Science and Business Media LLC. - 1758-9193. ; 15:1
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Tidskriftsartikel (refereegranskat)abstract
- BackgroundNeurofilament light (NfL) and neurogranin (Ng) are promising candidate AD biomarkers, reflecting axonal and synaptic damage, respectively. Since there is a need to understand the synaptic and axonal damage in preclinical Alzheimer's disease (AD), we aimed to determine the cerebrospinal fluid (CSF) levels of NfL and Ng in cognitively unimpaired elderly from the Gothenburg H70 Birth Cohort Studies classified according to the amyloid/tau/neurodegeneration (A/T/N) system.MethodsThe sample consisted of 258 cognitively unimpaired older adults (age 70, 129 women and 129 men) from the Gothenburg Birth Cohort Studies. We compared CSF NfL and Ng concentrations in A/T/N groups using Student's T-test and ANCOVA.ResultsCSF NfL concentration was higher in the A-T-N+ group (p=0.001) and the A-T+N+ group (p=0.006) compared with A-T-N-. CSF Ng concentration was higher in the A-T-N+, A-T+N+, A+T-N+, and A+T+N+ groups (p<0.0001) compared with A-T-N-. We found no difference in NfL or Ng concentration in A+ compared with A- (disregarding T- and N- status), whereas those with N+ had higher concentrations of NfL and Ng compared with N- (p<0.0001) (disregarding A- and T- status).ConclusionsCSF NfL and Ng concentrations are increased in cognitively normal older adults with biomarker evidence of tau pathology and neurodegeneration.
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| 2. |
- Arvidsson Rådestig, Maya, et al.
(författare)
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Subtle Differences in Cognition in 70-Year-Olds with Elevated Cerebrospinal Fluid Neurofilament Light and Neurogranin: A H70 Cross-Sectional Study
- 2023
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Ingår i: Journal of Alzheimers Disease. - : IOS Press. - 1387-2877 .- 1875-8908. ; 91:1, s. 291-303
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Tidskriftsartikel (refereegranskat)abstract
- Background: Most research on cerebrospinal fluid (CSF) neurofilament light protein (NfL) as a marker for neurodegeneration and neurogranin (Ng) for synaptic dysfunction has largely focused on clinical cohorts rather than population-based samples. Objective: We hypothesized that increased CSF levels of NfL and Ng are associated with subtle cognitive deficits in cognitively unimpaired (CU) older adults. Methods: The sample was derived from the Gothenburg H70 Birth Cohort Studies and comprised 258 CU 70-year-olds, with a Clinical Dementia Rating score of zero. All participants underwent extensive cognitive testing. CSF levels of NfL and Ng, as well as amyloid beta(1-42), total tau, and phosphorylated tau, were measured. Results: Participants with high CSF NfL performed worse in one memory-based test (Immediate recall, p = 0.013) and a language test (FAS, p = 0.016). Individuals with high CSF Ng performed worse on the memory-based test Supra Span (p = 0.035). When stratified according to CSF tau and A beta(42) concentrations, participants with high NfL and increased tau performed worse on a memory test than participants normal tau concentrations (Delayed recall, p = 0.003). In participants with high NfL, those with pathologic A beta(42) concentrations performed worse on the Delayed recall memory (p = 0.044). In the high Ng group, participants with pathological A beta(42) concentrations had lower MMSE scores (p = 0.027). However, in regression analysis we found no linear correlations between CSF NfL or CSF Ng in relation to cognitive tests when controlled for important co-variates. Conclusion: Markers of neurodegeneration and synaptic pathology might be associated with subtle signs of cognitive decline in a population-based sample of 70-year-olds.
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| 3. |
- Bartlett, Jonathan W, et al.
(författare)
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Determining cut-points for Alzheimer's disease biomarkers: statistical issues, methods and challenges.
- 2012
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Ingår i: Biomarkers in medicine. - : Future Medicine Ltd. - 1752-0371 .- 1752-0363. ; 6:4, s. 391-400
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Tidskriftsartikel (refereegranskat)abstract
- New proposed criteria for the clinical diagnosis of Alzheimer's disease increasingly incorporate biomarkers, most of which are normally measured on a continuous scale. Operationalizing such criteria thus requires continuous biomarkers to be dichotomized, which in turns requires the selection of a cut-point at which to dichotomize. In this article, we review the statistical principles underlying the choice of cut-points, describe some of the most commonly adopted statistical approaches used to estimate cut-points, highlight potential pitfalls in some of the approaches and characterize in what sense the estimated cut-point from each approach is optimal. We also emphasize that how a cut-point is selected must be made in reference to how the resulting dichotomized biomarker is to be used, and in particular what actions will follow from a positive or negative test result.
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| 4. |
- Bridel, Claire, et al.
(författare)
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Diagnostic Value of Cerebrospinal Fluid Neurofilament Light Protein in Neurology : A Systematic Review and Meta-analysis
- 2019
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Ingår i: JAMA Neurology. - : American Medical Association (AMA). - 2168-6149 .- 2168-6157. ; 76:9, s. 1035-1048
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Forskningsöversikt (refereegranskat)abstract
- Importance Neurofilament light protein (NfL) is elevated in cerebrospinal fluid (CSF) of a number of neurological conditions compared with healthy controls (HC) and is a candidate biomarker for neuroaxonal damage. The influence of age and sex is largely unknown, and levels across neurological disorders have not been compared systematically to date.Objectives To assess the associations of age, sex, and diagnosis with NfL in CSF (cNfL) and to evaluate its potential in discriminating clinically similar conditions.Data Sources PubMed was searched for studies published between January 1, 2006, and January 1, 2016, reporting cNfL levels (using the search terms neurofilament light and cerebrospinal fluid) in neurological or psychiatric conditions and/or in HC.Study Selection Studies reporting NfL levels measured in lumbar CSF using a commercially available immunoassay, as well as age and sex.Data Extraction and Synthesis Individual-level data were requested from study authors. Generalized linear mixed-effects models were used to estimate the fixed effects of age, sex, and diagnosis on log-transformed NfL levels, with cohort of origin modeled as a random intercept.Main Outcome and Measure The cNfL levels adjusted for age and sex across diagnoses.Results Data were collected for 10 059 individuals (mean [SD] age, 59.7 [18.8] years; 54.1% female). Thirty-five diagnoses were identified, including inflammatory diseases of the central nervous system (n = 2795), dementias and predementia stages (n = 4284), parkinsonian disorders (n = 984), and HC (n = 1332). The cNfL was elevated compared with HC in a majority of neurological conditions studied. Highest levels were observed in cognitively impaired HIV-positive individuals (iHIV), amyotrophic lateral sclerosis, frontotemporal dementia (FTD), and Huntington disease. In 33.3% of diagnoses, including HC, multiple sclerosis, Alzheimer disease (AD), and Parkinson disease (PD), cNfL was higher in men than women. The cNfL increased with age in HC and a majority of neurological conditions, although the association was strongest in HC. The cNfL overlapped in most clinically similar diagnoses except for FTD and iHIV, which segregated from other dementias, and PD, which segregated from atypical parkinsonian syndromes.Conclusions and Relevance These data support the use of cNfL as a biomarker of neuroaxonal damage and indicate that age-specific and sex-specific (and in some cases disease-specific) reference values may be needed. The cNfL has potential to assist the differentiation of FTD from AD and PD from atypical parkinsonian syndromes.
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| 5. |
- Dittrich, Anna, 1972, et al.
(författare)
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Association of Chronic Kidney Disease With Plasma NfL and Other Biomarkers of Neurodegeneration: The H70 Birth Cohort Study in Gothenburg.
- 2023
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Ingår i: Neurology. - 1526-632X. ; 101:3, s. e277-e288
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Tidskriftsartikel (refereegranskat)abstract
- Studies associate chronic kidney disease (CKD) with neurodegeneration. This study investigated the relationship between kidney function, blood, CSF, and structural brain MRI markers of neurodegeneration in a sample including individuals with and without CKD.Participants from the Gothenburg H70 Birth Cohort Study, with data on plasma neurofilament light (P-NfL), estimated glomerular filtration rate (eGFR), and structural brain MRI were included. Participants were invited to also have the CSF collected. The primary endpoint of this study was to determine any association between CKD and P-NfL. Secondary endpoints included cross-sectional associations between CKD, eGFR, and CSF-derived and MRI-derived markers of neurodegeneration and Alzheimer disease (AD) pathology (MRI: cortical thickness, hippocampal volume, lateral ventricle volume, and white matter lesion volume; CSF: β-amyloid (Aβ) 42, Aβ42/40, Aβ42/p-tau, t-tau, p-tau, and NfL). Participants with P-NfL and eGFR at baseline were re-examined on eGFR, 5.5 (5.3-6.1) years (median; IQR) after the first visit, and the predictive value of P-NfL levels on incident CKD was estimated longitudinally, using a Cox proportional hazards model.We included 744 participants, 668 without CKD (age 71 [70-71] years, 50% males) and 76 with CKD (age 71 [70-71] years, 39% males). Biomarkers from the CSF were analyzed in 313 participants. A total of 558 individuals returned for a re-examination of eGFR (75% response rate, age 76 [76; 77] years, 48% males, 76 new cases of CKD). Participants with CKD had higher P-NfL levels than those with normal kidney function (median; 18.8 vs 14.1 pg/mL, p < 0.001), while MRI and CSF markers were similar between the groups. P-NfL was independently associated with CKD after adjustment for confounding variables, including hypertension and diabetes (OR; 3.231, p < 0.001), in a logistic regression model. eGFR and CSF Aβ 42/40: R = 0.23, p = 0.004 correlated in participants with Aβ42 pathology. P-NfL levels in the highest quartile were associated with incident CKD at follow-up (HR; 2.39 [1.21: 4.72]).In a community-based cohort of 70-year olds, P-NfL was associated with both prevalent and incident CKD, while CSF and/or imaging measures did not differ by CKD status. Participants with CKD and dementia presented similar levels of P-NfL.
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| 6. |
- Gatenholm, Birgitta, 1986, et al.
(författare)
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Peptidomic analysis of cartilage and subchondral bone in OA patients
- 2019
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Ingår i: European Journal of Clinical Investigation. - : Wiley. - 0014-2972 .- 1365-2362. ; 49:5
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Tidskriftsartikel (refereegranskat)abstract
- © 2019 Stichting European Society for Clinical Investigation Journal Foundation Background: The objective of this study was to develop a method for directly analysing osteochondral samples straight out of the operating room without cell culturing, thereby enabling identification of potential peptide biomarkers to better understand the mechanisms involved in the development of osteoarthritis and pain. Material and Methods: Osteochondral plugs from wounded and macroscopically nonwounded zones of the femur condyle were collected from six patients with manifest osteoarthritis (OA) undergoing total knee arthroplasty (TKA). The samples were demineralized and supernatant was collected and isotopically marked with Tandem Mass Tag (TMT) labelling and analysed using liquid chromatography coupled with tandem mass spectrometry LC-MS/MS. Results: Using peptidomics, 6292 endogenous peptides were identified. Five hundred sixty-six peptides (8 identified endogenous peptides) differed significantly (P-value 0.10) from wounded zones compared to nonwounded zones. Conclusion: This pilot study shows promising results for enabling peptidomic analysis of cartilage and bone straight out of the operating room. With further refinement, peptidomics can potentially become a diagnostic tool for OA, and improve the knowledge of disease progression and genesis of pain.
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| 7. |
- Hansson, Karl, 1985, et al.
(författare)
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Expanding the cerebrospinal fluid endopeptidome
- 2017
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Ingår i: Proteomics. - : Wiley. - 1615-9853. ; 17:5
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Tidskriftsartikel (refereegranskat)abstract
- Biomarkers of neurodegenerative disorders are needed to assist in diagnosis, to monitor disease progression and therapeutic interventions, and to provide insight into disease mechanisms. One route to identify such biomarkers is by proteomic and peptidomic analysis of cerebrospinal fluid (CSF). In the current study, we performed an in-depth analysis of the human CSF endopeptidome to establish an inventory thatmay serve as a basis for future targeted biomarker studies. High-pH RP HPLC was employed for off-line sample prefractionation followed by low-pH nano-LC-MS analysis. Different software programs and scoring algorithms for peptide identification were employed and compared. A total of 18 031 endogenous peptides were identified at a FDR of 1%, increasing the number of known endogenous CSF peptides 10fold compared to previous studies. The peptides were derived from 2 053 proteins of which more than 60 have been linked to neurodegeneration. Notably, among the findings were six peptides derived from microtubule-associated protein tau, three of which span the diagnostically interesting threonine-181 (Tau-F isoform). Also, 213 peptides from amyloid precursor protein were identified, 58 of which were partially or completely within the sequence of amyloid beta 1-40/42, as well as 109 peptides from apolipoprotein E, spanning sequences that discriminate between the E2/E3/E4 isoforms of the protein.
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| 8. |
- Hansson, Karl, 1985, et al.
(författare)
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Sample Preparation for Endopeptidomic Analysis in Human Cerebrospinal Fluid
- 2017
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Ingår i: Jove-Journal of Visualized Experiments. - : MyJove Corporation. - 1940-087X. ; :130
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Tidskriftsartikel (refereegranskat)abstract
- This protocol describes a method developed to identify endogenous peptides in human cerebrospinal fluid (CSF). For this purpose, a previously developed method based on molecular weight cut-off (MWCO) filtration and mass spectrometric analysis was combined with an offline high-pH reverse phase HPLC pre-fractionation step. Secretion into CSF is the main pathway for removal of molecules shed by cells of the central nervous system. Thus, many processes in the central nervous system are reflected in the CSF, rendering it a valuable diagnostic fluid. CSF has a complex composition, containing proteins that span a concentration range of 8-9 orders of magnitude. Besides proteins, previous studies have also demonstrated the presence of a large number of endogenous peptides. While less extensively studied than proteins, these may also hold potential interest as biomarkers. Endogenous peptides were separated from the CSF protein content through MWCO filtration. By removing a majority of the protein content from the sample, it is possible to increase the sample volume studied and thereby also the total amount of the endogenous peptides. The complexity of the filtrated peptide mixture was addressed by including a reverse phase (RP) HPLC pre-fractionation step at alkaline pH prior to LC-MS analysis. The fractionation was combined with a simple concatenation scheme where 60 fractions were pooled into 12, analysis time consumption could thereby be reduced while still largely avoiding co-elution. Automated peptide identification was performed by using three different peptide/protein identification software programs and subsequently combining the results. The different programs were complementary rather than comparable with less than 15% of the identifications overlapped between the three.
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| 9. |
- Lautner, Ronald, et al.
(författare)
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Preclinical effects of APOE epsilon 4 on cerebrospinal fluid A beta 42 concentrations
- 2017
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Ingår i: Alzheimers Research & Therapy. - : Springer Science and Business Media LLC. - 1758-9193. ; 9
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Tidskriftsartikel (refereegranskat)abstract
- Background: From earlier studies it is known that the APOE epsilon 2/epsilon 3/epsilon 4 polymorphism modulates the concentrations of cerebrospinal fluid (CSF) beta-amyloid(1-42) (A beta 42) in patients with cognitive decline due to Alzheimer's disease (AD), as well as in cognitively healthy controls. Here, in a large cohort consisting solely of cognitively healthy individuals, we aimed to evaluate how the effect of APOE on CSF A beta 42 varies by age, to understand the association between APOE and the onset of preclinical AD. Methods: APOE genotype and CSF A beta 42 concentration were determined in a cohort comprising 716 cognitively healthy individuals aged 17-99 from nine different clinical research centers. Results: CSF concentrations of A beta 42 were lower in APOE epsilon 4 carriers than in noncarriers in a gene dose-dependent manner. The effect of APOE epsilon 4 on CSF A beta 42 was age dependent. The age at which CSF A beta 42 concentrations started to decrease was estimated at 50 years in APOE epsilon 4-negative individuals and 43 years in heterozygous APOE epsilon 4 carriers. Homozygous APOE epsilon 4 carriers showed a steady decline in CSF A beta 42 concentrations with increasing age throughout the examined age span. Conclusions: People possessing the APOE epsilon 4 allele start to show a decrease in CSF A beta 42 concentration almost a decade before APOE epsilon 4 noncarriers already in early middle age. Homozygous APOE epsilon 4 carriers might deposit A beta 42 throughout the examined age span. These results suggest that there is an APOE epsilon 4-dependent period of early alterations in amyloid homeostasis, when amyloid slowly accumulates, that several years later, together with other downstream pathological events such as tau pathology, translates into cognitive decline.
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| 10. |
- Lautner, Ronald, et al.
(författare)
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Preclinical effects of APOE ϵ4 on cerebrospinal fluid Aβ42 concentrations
- 2017
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Ingår i: Alzheimer's Research and Therapy. - : Springer Science and Business Media LLC. - 1758-9193. ; 9:1
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Tidskriftsartikel (refereegranskat)abstract
- Background: From earlier studies it is known that the APOE ϵ2/ϵ3/ϵ4 polymorphism modulates the concentrations of cerebrospinal fluid (CSF) beta-amyloid1-42 (Aβ42) in patients with cognitive decline due to Alzheimer's disease (AD), as well as in cognitively healthy controls. Here, in a large cohort consisting solely of cognitively healthy individuals, we aimed to evaluate how the effect of APOE on CSF Aβ42 varies by age, to understand the association between APOE and the onset of preclinical AD. Methods: APOE genotype and CSF Aβ42 concentration were determined in a cohort comprising 716 cognitively healthy individuals aged 17-99 from nine different clinical research centers. Results: CSF concentrations of Aβ42 were lower in APOE ϵ4 carriers than in noncarriers in a gene dose-dependent manner. The effect of APOE ϵ4 on CSF Aβ42 was age dependent. The age at which CSF Aβ42 concentrations started to decrease was estimated at 50 years in APOE ϵ4-negative individuals and 43 years in heterozygous APOE ϵ4 carriers. Homozygous APOE ϵ4 carriers showed a steady decline in CSF Aβ42 concentrations with increasing age throughout the examined age span. Conclusions: People possessing the APOE ϵ4 allele start to show a decrease in CSF Aβ42 concentration almost a decade before APOE ϵ4 noncarriers already in early middle age. Homozygous APOE ϵ4 carriers might deposit Aβ42 throughout the examined age span. These results suggest that there is an APOE ϵ4-dependent period of early alterations in amyloid homeostasis, when amyloid slowly accumulates, that several years later, together with other downstream pathological events such as tau pathology, translates into cognitive decline.
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